While automation has steadily increased in many technology spaces, a variety of machines still exist which require labor-intensive manual monitoring or adjustment. Even where some automation is present, it may be primitive, low-performance, or inefficient in comparison with other systems with which it interacts (e.g., causing a bottleneck or point of friction in a production line). In one example, hot melt dispensing systems include a variety of parameters which must be managed during operation. While a hopper or tank can be filled and a temperature of a melter set, other variables, such as system pressure, lack automation.
This lack of automation or remote control poses a number of drawbacks. It is inconvenient and expensive to staff operators to individual machines in a production line or other environments. Moreover, those operators are exposed to hazards which could be avoided if automation were available. Further, the accuracy and reliability of adjustments may be improved through the implementation of consistent algorithms utilized in machine control.
Non-automated controllers may be adjusted by an operator using a tool such as a hex wrench. This requires the operator to physically access the device and carry the appropriate tool to make the adjustment. The screw (or other element) with which the tool interacts can become worn or stripped and likewise more difficult to precisely adjust through continued use. Human adjustments are also susceptible to estimation or inexact setting. Even where some parameter references are present (e.g., numbered lines, clicks), a margin of error inheres in human operation—based on the operator's knowledge, judgment, and physical capabilities—which can add substantial variability to a process.
Some alternative controllers may be operated with an air pilot. While an air pilot may be used to reduce or remove human variability, other drawbacks exist. Air pilot controllers require inclusion of a line for clean air, thereby limiting their placement and mobility in a production environment while increasing maintenance burden and cost. Further, the performance of air piloted controllers (as measured by, e.g., linearity, resolution, hysteresis, and stiction) may be inferior to that of alternatives.
There is a need, therefore, for high-performance, automated pressure control systems which can be inexpensively integrated into new hot melt dispensing systems or inexpensively retrofitted to existing hot melt dispensing systems. With greater consistency and controllability, more precise “recipes” can be defined and utilized in production. Such recipes depend on carefully controlling pressure in addition to other product parameters. These parameters can be defined and followed automatically using high-performance, automated pressure control systems. These parameters can also be maintained or adjusted even when other parameters change, thereby increasing consistency in products. Thus, in addition to increasing performance, such solutions can also reduce costs, not only based on equipment or labor expenses but by reducing product defects resulting from variability.